Permutational switch



6 Sheets-Sheet 1 G. W. M CHEYNE PERMUTATIONAL SWITCH Dec. 10, 1957 FiledApril 25, 1952 w. t 2 m. 2 m. E o. m m h w n v m N u NB K M 2 o irf1 i 0ow. MWWfi I I I I I I I I i i I i I I I 1 l I I I I O: m0- nw NINVENTOR. GEORGE W. MAC CHEYNE BY]! ATTORNEY Dec. 10, 1957 Filed April25, 1952 G. W. M CHEYNE PERMUTATIONAL SWITCH lOl 6 Sheets-Sheet 2INVENTOR. GEORGE W. MAC CHEYNE m'jf ATTORNEY Dec. 10, 1957 G. W.MaccHEYNE PERMUTATIONAL SWITCH 6 Sheets-Sheet 3 Filed April 25, 1952 I II I I I f I O 6 V 4 IllIII/IllIIIII/IIIIl/IIIIII/I/Im/I/ INVENTOR.GEORGE W. MAC CHEYNE ATTORNEY Dec. 10, 1957 G. w. M CHEYNE 2,815,586

PERMUTATIONAL SWITCH 6 Sheets-Sheet 4 Filed April 25, 1952 FIG. 5

INVENTOR. GEORGE w. MAC CH EYNE Jfd-ww ATTORNEY Dec. 10, 1957 G. w. MCHEYNE 2,815,586

PERMUTATIONAL SWITCH Filed April 25. 1952 e Sheets-Sheet 5 INVENTOR.GEORGE w MAC CHEYNE ATTORNEY Dean 10, 1957 G. W. M CHEYNE 2,815,586

PERMUTATIONAL SWITCH Filed April 25, 1952 e Sheets-Sheet aIIIIIII/MIIIII/I/IIIIIIII/II/I/I/I/I/ INVENTOR. GEORGE MACCHEYNEATTORNEY PERMUTATIONAL SWITCH George W. MacCheyne, Webster, N. Y.,assignor, by mesne assignments, to General Dynamics Corporation, acorporation of Delaware Application April 25, B52, Serial No. 284,408

11 Claims. (Cl. 35-4) My invention relates to electrical switches, andparticularly to electrical switches of the permutational type. By aswitch of the permutational type, I mean a switch in which each of aplurality of input conductors may be interconnected with any desiredones of a plurality of output conductors.

Switches of the permutational type find special application incryptographic devices in which electrical circuits are employed. In suchdevices, it is known that a message may be enciphered by interconnectingthe input conductors with the output conductors in an order dependingupon the cipher being used. Since ciphers may be broken, it is desirablethat the particular cipher employed during one period of time be changedto another cipher for use during another interval of time. In electricalcryptographic devices, this means that it is necessary to change theorder of interconnection between input and output conductors in order toproduce the new cipher. Such changes have been accomplished by codewheels prior to my invention, but such devices are in general too bulky,handle too small a number of interconnections, or require too much timeto change from one cipher to another. In some cases, not all of thepermutations of possible interconnections may be obtained by theinterconnecting devices.

It is accordingly an object of my invention to provide a permutationalswitch of a new and advantageous type, in which all permutations of thepossible interconnections are available.

It is another object of my invention to provide a permutational switchin which a given order of interconnections between input and outputconductors can quickly and easily be changed to a diiierent order ofinterconnections.

It is another object of my invention to provide a permutational switchcapable of handling a large number of input and output conductors, yetwhich achieves a high degree of space utilization.

It is still another object of my invention to provide a permutationalswitch which may be mounted behind a control panel with minimum frontalprotrusion, yet which may easily be set for a given order ofinterconnections.

It is yet another object of my invention to provide a permutationalswitch of compact yet rugged construction which can be locked againstaccidental alteration of the order of interconnections desired.

Further objects and advantages of my invention will become apparent asthe following description proceeds, and the features of novelty whichcharacterize my invention will be pointed out with particularity in theclaims annexed to and forming a part of this specification.

For a better understanding of my invention, reference may be had to theaccompanying drawing in which Fig. 1 is a front-of-panel view of oneembodiment of my invention;

Fig. 2 is a top view of the embodiment of Fig. 1;

Fig. 3 is an end view of the embodiment shown in tates Patent Fig. 4 isa sectional view taken along the line 4-4 in Fig. 1;

Fig. 5 is a sectional view taken along the line 5-5 in Fig. 3;

Fig. 6 is a sectional view taken along line 6-6 in Fig. l; and

Fig. 7 is a sectional view taken along line 77 in Fig. 1.

The embodiment shown in the drawings permits eighteen incomingconductors to be connected with eighteen outgoing conductors in anydesired order. Those skilled in the art to which my invention appertainscan readily appreciate that more or fewer input or output conductors maybe accommodated in a permutational switch constructed according to myinvention. Furthermore, it is to be noted that in this specification, Iemploy the words input and output relative to conductors as a convenientdesignation, and not with an absolute electrical connotation. I havechosen to designate the eighteen incoming conductors by means of Arabicnumerals 1-18, and the eighteen outgoing conductors by means of lettersAS (omitting letter I). In accordance with my invention, incomingconductor 1 may be connected with any one of outgoing conductors AS,irrespective of the interconnections of any of the other incomingconductors. This independence of other interconnections is true of anysingle incoming conductor.

To avoid confusion with the conductor designation scheme set forthabove, I have chosen to explain my invention by a series of referencesymbols starting with 101.

The frontal appearance of a preferred embodiment of my invention isshown in Fig. l. The mechanism is mounted behind a front panel 101, witha portion of each of 18 thumb wheels, such as 102 for example,projecting through a slot 103 in the panel. Adjacent to each thumb wheelis an indicia member with letters AS engraved on its circumference. Inthe case of thumb wheel 102, the indicia member is represented by symbol104, and a portion thereof may be viewed through a window 105 formed inpanel 101. As may be seen from Fig. 1, thumb wheel 102 is shown in aposition such that the letter K may be viewed through window 105. Thisindicates that thumb wheel 102 has been set such that incoming conductor10 is interconnected with outgoing conductor K. The arrangement for eachof the 18 thumb wheels (there being one thumb wheel for each incomingconductor) may be identical to that provided for thumb wheel 102. Inview of this circumstance, the arrangement according to my invention ofthe present embodiment is described in this specification in detail withrespect to thumb wheel 102 and the parts cooperating therewith, it beingunderstood that the construction and operation of the other thumb wheelsand their accompanying parts may be substantially identical.

It is a feature of my invention that the particular order panyingdrawings, with its closed, or protective, position I being indicated inFigs. 1 and 4 by means of dashed lines.

Further in accordance with my invention, I may provide a locking lever107 which may be moved along a slot 108 to lock all thumb wheelssimultaneously against accidental alteration of the order ofinterconnection.-

Thus when locking lever 107 is at end 109 of the L- shaped slot 108, asshown in Fig. 1, all of the thumb wheels are locked against rotation. Tounlock the thumb wheels so that the order of interconnection may be al-I tered, locking lever 107 is moved to end 110 of slot 108.

It is- -a feature ofmy invention -that-door106 cannot-be closed andsecured in position unless locking lever 107 is at end 109 of slot 108,thus insuring that all of the thumb-wheels are secure' against rotationwhenever-the door is observed to be shut.

' The disposition. of par-tsin "Fig. L-may' be inspected in greaterdetail in Fig. 2. As shown here, door 106-is mounted on hinges Ill-and11:2, with mating' hinge 'mem ber 113 being mounted on panel 101. Alsovi'sible-in Fig. 2 'are the incomingconductors, that corresponding toincoming conductor being designated by reference symbol114. Incomingwires may be attached to-the incoming conductors by anysconvenientmeans,although I have chosen .to show-a hole. 115v in incoming conductor 114toassistin securing'a wire tomember 114. Incoming conductor114 may besecuredto a mounting member 116 made. .of insulatingmaterial by means ofscrews 117 or other convenient fastening means. Also shown in Fig. 2'are some of. the outgoing conductors; for example, the outgoingconductor corresponding (in 'the:present embodiment). to letter. K isdesignated by. reference symbol 118. As with the incoming conductors,each .of the outgoing conductors may. be provided with a wire-receivinghole to assist insecuring an outgoing wire to the outgoing conductor.Inthe case of outgoing conductor 118 the hole is designated by symbol119. Other. outgoing conductors visible in Fig. 2 are indicated-byreference symbols 120-123.and 124-126,.corresponding respectively(in thepresent embodiment) to the. outgoing conductors designated by letters 0,N, M, L,.and I, H, G.

In accordance with my invention, the outgoing conductors may beconnected to, or preferably formed integrally with, a plurality ofsegmental bars which form a stationary commutator of generallycylindrical configuration. These segmental bars are made of conductingmaterial, such as copper, and are preferably embedded in a mass ofplastic material which secures them against motion relative to eachother. I have illustrated the present embodiment of my invention asemploying the integral construction of segmental bars and outgoingconductors, and therefore a single reference symbol is used for both.The position ofthe commutator bars, such assegmental bar118, relative toeach other and to the mass of plastic material is best seen from thedashed outlines thereof in. Fig. 3. The bars are disposed parallel tothe. axis of the cylindrical configuration which forms the stationarycommutator. The stationary commutator is designated-by reference symbol127, and is disposed with i-tsdongitudinal axis. substantially parallelto the plane offront panel 101.

.Figs. 2 and 3 .illustrate how commutator 127 may be secured .inplacethrough attachment, as by screws 128, to insulatingendplates 129.Insulating end plates 129 in turn may, be secured, as by means of screws130, to end frame members-131 :of the switch. Front panel 101 may beattached to end frame members 131 by such convenient means as screws132'which pass-through the front panel and mate in tapped holes (notshown) in the end frame members. Frame members 131 may be positionedrelative to each other by means of longitudinal frame member 133,insulating mounting member 116, and spacing member 134.

Fig. 2 shows that each incoming conductor is provided with a relativelylong, forwardly-extending portion, this portion being designated in thecase of incoming conductor 114 by reference symbol 135. There is thusformed a contact spring whose contour may be examined in greater detailin the end view, Fig. 3. The spring contacts the outer periphery of aconductive ring, 136 (shown by dashed line). As illustrated in thesectional view, Fig. 4, ring 136, in turn carries bracket 137. Mountedon bracket 137 is a spring.'138 which in turn. maintains brush 139 inposition to contact commutator 127. -The particular bar being contactedin the drawingsis bar 118.

pointed "out earlier,- each of the segmental bars' isconnected to (or ispreferably formed integrally with) an outgoing conductoroutgoingconductor K in the case shown. Thus the conducting path from an incomingconductor such as 114 to an outgoing conductor such as K (symbol 118)may be understood from Fig. 4 to extend from conductor 114, springportion 135, conductive ring 136, bracket 137, spring 138 and brush 139to segmental bar 118.

Conductive ring 136 is secured to an insulating memher 140, as by meansof screws (not shown) or other convenient means. Proper location isobtained by fitting the center-hole in ring 136 onto anappropriately-dimensioned hub portion of insulating member 140. Fig. 5indicates the spatial relationship between conductive ring 136 andinsulating member 140. Thumb wheel 102 is positioned concentricallyabout insulating ring 140 and secured firmly thereto, as by means of keyand slot arrangement. All conductive rings of the switch are thus seento be disposed parallel to each other and coaxially with respect tocommutator 127.

Also revealed in Fig. 5 is the longitudinal contour of segmental bar118. This bar, like the other segmental bars of the stationarycommutator 127 is seen to have a series of raised portions 141 andundercut portions 142. This contour of the stationary commutator isreadily produced by the preferred method of manufacture, whichcontemplates holding the segmental bars in position and casting a massof plastic material around them. Upon hardening of the plastic material,the assembly may be placed in a lathe and turned down to produce thecontour shown. In this way, a series of parallel grooves, or undercutportions, may be formed circumferentially around stationary commutator127, thus exposing portions only of the segmental bars.

Secured to insulating ring 140 is a retaining ring comprising aplurality of arcuate segments. As shown in Fig. 7, I prefer to employthree such segments, 143, 144, and 145, each covering approximately Ifurther prefer that they be attached to insulating ring by means ofscrews 146. Although other means of fastening may be employed, I preferthat screws be used because assembly or disassembly of the switch may beexpedited thereby.

Returning now to Fig. 5, it may be observed that the retaining ringsegments are formed with an inwardlyextending portion 149, which formsan annular ridge mating with grooved portion 142. Also shown in Fig. 5is a separator ring 147 adjacent the retaining ring 143. Ring 147 servesas insulation between the indicia portion 104 of thumb wheel 102, whichis preferably made of metal to obtain long-wearing qualities, andcontact spring 148 of the next adjacent input conductor. Separator ring147 is preferably formed of friction-reducing material in order toprevent movement of adjacent parts when a given thumb wheel ismanipulated.

A feature of my invention-is the use of a detent means which servesaccurately to position brush 139 in the center of the particularsegmental bar portion chosen. As shown in Fig. 4, a lever arm150individual to a particular thumb wheel (in this case wheel 102) ispivoted about a common axle 151. Arm 1'50 supports an idler wheel 152. Aspring 153 compressed between spring seats 154 and 155 biases wheel 152against the outer circumference of thumb wheel 102. Thiscircumference'is contoured with radial undulations, or serrations, witha rounded portion, such as 156, being formed at the valleys betweenserrations. The serrations, in projecting through slot 103 in frontpanel 101, provide a convenient means for thumb rotation of wheel 102.The pressure of wheel 152 on these serrations provides an addedrotational force in addition to thumb force on the wheel, this addedforce being present until wheel 152 drops into one of the roundedportions.

'As pointed out earlier, I may'alsoprovide a means for simultaneouslylocking all of the thumb wheels against rotation. Fig. 4 shows howlocking lever 107 is secured to lock bar 156, as by means of a threadedportion 157 of the former mating with a threaded hole 158 in the latter.I may, in addition, prefer to retain locking lever 1m in locking bar 156by means of a set screw 159.

The longitudinal arrangement of the locking means may be seen in Fig. 6.Lock bar 156 may be moved parallel to the axis of stationary commutator127 by locking lever 1W7. Lock bar 155 has alternate recessed andunrecessed, or brake, portions, such as 169 and 161, respectively. Thuswhen locking lever 107 is in the unlocked position (that is, at end 110of slot 108; see Fig. 1) the recessed portions of lock bar 156 are eachopposite a corresponding one of the thumb wheels. Locking bar 156 ispreferably biased, as by means of spring 162 (Fig. 6) to move toward theunlocked position.

Upon moving locking lever 107 to the locked position (end 1 99 of slotres; see Fig. 1), an unrecessed portion of lock bar 156 is broughtopposite each of the thumb wheels. The unrecessed portions consequentlymate with the rounded portions in the valleys between the serrationsformed in the thumb wheels. By reason of this feature, it may be seenthat look bar 156' cannot be placed in the locked position unless eachof the thumb wheels is accurately positioned on a particular one of thesegmental bars of the commutator 127. Furthermore, it may be observedfrom Fig. 4 that door 196' cannot be placed in the closed positionindicated by dotted line 163 unless locking lever 1697 is in the lockedposition (end 109 of slot Hi8, Fig. 1). Conversely, door 106, when shut,prevents locking lever 16'! from moving to end 110 of slot 10%. Thisfeature insures that any time door IE6 is locked shut every thumb wheelis accurately positioned and locked against rotation.

Door 1% is preferably retained in the closed position by means of aconventional snap-slide fastener comprising handle Ill-5 (Pig. 6),support 165, slide 166, and mating stud 167. These parts may beprotected by an inner cover 163 held in place by a convenient means, asscrews 169. Snap-slide fasteners are well-known and hence are notdetailed here.

While I have shown and described my invention as applied to a specificembodiment thereof, other modifications will readily occur to thoseskilled in the art. I do not, therefore, desire my invention. to belimited to the specific arrangement shown and described, and I intend inthe appended claims to cover all modifications within the spirit andscope of my invention.

What I claim is:

1. In a permutational switch device, the combination of a plurality ofinput conductors; a plurality of output conductors; a stationarycommutator of generally cylindrical configuration having segmental barsdisposed paraL lel to the axis of said cylindrical configuration andembedded in a mass of electrical insulating material such that portionsonly of said bars are exposed at the circumferential surface of saidcommutator, each of said bars being connected to individual ones of saidoutput conductors, said commutator having a plurality of circumferentialgrooves formed therein, each of said grooves being located betweenadjacent ones of said exposed portions of said bars; a plurality ofconductive rings, each of said rings being disposed parallel to eachother and coaxial with respect to said commutator, and each of saidrings further having attached thereto insulating means including anannular ridge mating with a corresponding one of said grooves, wherebysaid rings are individually prevented from substantial movement in anaxial direction relative to said commutator; each of said rings having abrush mounted thereon, each said brush being positioned for contact withone of said exposed portions of one of said bars at a time; a pluralityof stationarilymounted contacts, each of said plurality of contactsbeing connected to individual ones of said input conductors 6 and beingmounted to bear on a corresponding one of said rings, whereby throughrotation of said rings any one of said input conductors can be broughtinto conductive relationship with one of said exposed portions of one ofsaid bars, and hence with one of said output conductors.

2. in a permutational switch device, the combination of a plurality ofinput conductors; a plurality of output conductors; a stationarycommutator of generally cylin-- drical configuration having segmentalbars disposed paral-- lel to the axis of said cylindrical configurationand embedded in a mass of electrical insulating material such thatportions only of said bars are exposed at the circumferential surface ofsaid commutator, each of said bars being connected to individual ones ofsaid output conductors, said commutator having a plurality ofcircumferential grooves formed therein, each of said grooves beinglocated between adjacent ones of said exposed portions of said bars; aplurality of conductive rings, each of said rings being disposedparallel to each other and coaxially with respect to said commutator; aplurality of insulating rings, each of said insulating rings beingattached to an individual one of said conductive rings and having anannular ridge mating with a corre sponding one of said grooves, each ofsaid insulating rings being made in three arcuate segments, each saidarcuate segment being independently attached to the corresponding saidconductive ring and proportioned to permit removal of said insulatingring from said groove through removal of only one of said arcuatesegments; each of said conductive rings having a brush mounted thereon,each said brush being positioned for contact with one of said exposedportions of one of said bars at a time; a plurality ofstationarily-mounted contacts, each of said contacts being connected toindividual ones of said input conductors and being mounted to bear on acorresponding one of said conductive rings, whereby through rotation ofsaid conductive rings any one of said input conductors can be broughtinto conductive relationship with one of said exposed portions of one ofsaid bars, and hence with one of said output conductors.

3. In a permutational switch device, the combination of a plurality ofinput conductors; a plurality of output conductors; a stationarycommutator having a plurality of segments, each of said segments beingconnected to individual ones of said output conductors; a plurality ofconductive rings supported for rotation independent of each other aboutsaid commutator, the number of rings being equal to the number of saidinput conductors; each of said rin-gs having a brush mounted thereon,each said brush being positioned for contact with a portion of one ofsaid segments at a time; a plurality of stationarily-mounted contacts,each of said plurality of contacts being connected to individual ones ofsaid input conductors and being mounted to bear on a corresponding oneof said rings; a front panel having its plane substantiarly parallel tothe longitudinal axis of said commutator; a thumb wheel attached to eachof said rings, each said thumb wheel being positioned to project forconvenient thumb actuation through said panel, whereby through rotationof various ones of said thumb wheels, individual ones of said brushescan be brought into contact with individual ones of said segments andtherefore individual ones of said input conductors can be brought intoconductive relationship with individual ones of said output conductors.

4. In a permutational switch device, the combination of a plurality ofinput conductors; a plurality of output conductors; a stationarycommutator having a plurality of segments, each of said segments beingconnected to individual ones of said output conductors; a plurality ofconductive rings supported for rotation independent of each other aboutsaid commutator, the number of rings being equal to the number of saidinput conductors; each of said rings having a brush mounted thereon,each said brush being positioned for contact with a portion of one ofsaid segments at a time; a plurality of stationarily-mounted contacts,each of said plurality of contacts being connected to individual ones ofsaid input conductors and being mounted to bear on a corresponding oneof said rings; a generally wheel-shaped member attached to each saidring, each said member having multiple indentations around itscircumference, said indentations being spaced apart by the same angularproportion as said segments; detent means operating substantiallyequally against said indentations of each said wheel independent of theindentations in others of said wheels, whereby any of said brushes canbe brought into contact with any one of said segments with enhancedsurety by reason of said detent means positioning said brush withprecision on a given one of said segments.

5. In a permutational switch device, the combination of a plurality ofinput conductors; a plurality of output conductors; a stationarycommutator having a plurality of segments, each of said segments beingconnected to individual ones of said output conductors; a plurality ofconductive rings supported for rotation independent of each other aboutsaid commutator, the number of rings being equal to the number of saidinput conductors; each of said rings having a brush mounted thereon,each said brush being positioned for contact with a portion of one ofsaid segments at a time; a plurality of stationarilymounted contacts,each of said plurality of contacts being connected to individual ones ofsaid input conductors and being mounted to bear on a corresponding oneof said rings; a front panel having its plane substantially parallel tothe longitudinal axis of said commutator; a thumb wheel attached to eachof said rings, each said thumb wheel having radial undulations about itscircumferential edge and projecting through said panel for convenientthumb actuation, whereby through rotation of various ones of said thumbwheels, individual ones of said brushes can be brought into contact withindividual ones of said segments and therefore individual ones of saidinput conductors can be brought into conductive relationship withindividual ones of said output conductors.

6. In a permutational switch device, the combination of a plurality ofinput conductors; a plurality of output conductors; a stationarycommutator having a plurality of segments, each of said segments beingconnected to individual ones of said output conductors; -a plurality ofconductive rings supported for rotation independent of each otheraboutsaid commutator, the number of rings being equal to the number ofsaid input conductors; each of said rings having a brush mountedthereon, each said brush being positioned for contact with a portion ofone of said segments at a time; a plurality of stationarilymountedcontacts, each of said plurality of contacts being connected toindividual ones of said input conductors and being mounted to bear on acorresponding one of said rings; a front panel having its planesubstantially parallel to the longitudinal axis of said commutator; athumb wheel attached to each of said rings, each said thumb wheel havingradial undulations about its circumferential edge and projecting throughsa-idpa nel :for convenient thumb actuation; detent means individual toeach said thumb wheel and operative against said undulations to positioneach individual one of said rings for optimum contact between the brushcarried by said one ring and the particular one of said segments ,to becontacted, whereby through rotation of said rings any one of said inputconductors can be brought into conductive relationship with any one ofsaid output conductors.

7. In a pcrmutational switch device, the combination of a plurality ofinput conductors; a plurality of, output conductors; a stationarycommutator having a plurality of segments, each of said segments'beingconnected to indiyidualwones of said outputconductors; apluralityof conductive rings supported for rotation independent of each otherabout said commutator, the number of rings being equal to the number ofsaid input conductors; each of said rings having a brush mountedthereon, each said brush being positioned for contact with a portion ofone of said segments at a time; a plurality of stationarilymountedcontacts, each of said plurality of contact being connected toindividual ones of said input conductors and being mounted to bear on acorresponding one of said rings; a front panel having its planesubstantially parallel to the longitudinal axis of said commutator; athumb wheel attached to each of said rings, each said thumb wheel havingradial undulations about its circumferential edge and projecting throughsaid panel for convenient thumb actuation; an indicia member individualto each said ring arranged adjacent to said thumb wheel and mounted forintegral rotation therewith; indicia individual to each said ring markedaround the circumference of the particular indicia member associatedwith said each ring; a plurality of openings in said panel, each saidopening being individual to one of said indicia members and positionedto permit a view of a portion of said indicia marked on said individualones of said indicia members, whereby said thumb wheels can be actuatedto various angular positions relative to said commutator, thereby tointerconnect particular ones of said input conductors with particularones of said output conductors, and the combination of interconnectionschosen can be readily and visually identified from the front of saidpanel.

8. In a permutational switch device, the combination of a plurality ofinput conductors; a plurality of output conductors; a stationarycommutator having a plurality of segments, each of said segments beingconnected to individual ones of said output conductors; a plurality ofconductive rings supported for rotation independent of each other aboutsaid commutator, the number of rings being equal to the number of saidinput conductors; each of said rings having a brush mounted thereon,each said brush being positioned for contact with a portion of one ofsaid segments at a time; a plurality of stationarilymounted contacts,each of said plurality of contacts being connected to individual ones ofsaid input conductors and being mounted to bear on a corresponding oneof said rings, whereby through rotation of said rings any one of saidinput conductors can be brought into conductive relationship with anyone of said output conductors; and means for locking said rings againstrotation during use and for unlocking them during setting.

9. In a permutational switch device, the combination of a plurality ofinput conductors; a plurality of output conductors; a stationarycommutator having a plurality of segments, each of said segments beingconnected to individual ones of said output conductors; a plurality ofconductive rings supported for rotation independent of each other aboutsaid commutator, the number of rings being equal to the number of saidinput conductors; eachof said rings having a brush mounted thereon, eachsaid brush being positioned for contact with a portion of one of saidsegments at a time; a plurality of stationarily-mounted contacts, eachof said plurality of contacts being connected to individual ones of saidinput conductors and being mounted to bear on a corresponding one ofsaid rings, whereby through rotation of said rings any one of said inputconductors can be brought into conductive relationship with any one ofsaid output conductors; and means for simultaneously locking all of saidrings against rotation during use and for simultaneously unlocking allof said rings during setting.

10. In a permutational switch device, the combination a plurality ofinput conductors; a plurality of output conductors; a stationarycommutator having a plurality of segmentsv each of said segments beingconnected to individual ones of said output conductors; a plurality ofconductive rings supported for rotation independent of each other aboutsaid commutator, the number of rings being equal to the number of saidinput conductors; each of said rings having a brush mounted thereon,each said brush being positioned for contact with a portion of one ofsaid segments at a time; a plurality of stationarily-mounted contacts,each of said plurality of contacts being connected to individual ones ofsaid input conductors and being mounted to bear on a corresponding oneof said rings; a front panel having its plane substantially parallel tothe longitudinal axis of said commutator; a brake portion attached toeach of said rings; a locking bar spring biased to engage each of saidbrake portions and so to prevent rotation of said rings; and a lockinglever operable from the front of said panel and having lock and unlockpositions, said locking lever being operative in said one lock positionto counteract and maintain counteracted said spring bias on said lockingbar, thereby freeing said rings for rotation relative to saidcommutator, said locking lever being further operative in said lockposition to remove said counteraction of said spring bias and so to lockall of said rings against rotation.

11. In a permutational switch device, the combination of a plurality ofinput conductors; a plurality of output conductors; a stationarycommutator having a plurality of segments, each of said segments beingconnected to individual ones of said output conductors; a plurality ofconductive rings supported for rotation independent of each other aboutsaid commutator, the number of rings being equal to the number of saidinput conductors; each of said rings having a brush mounted thereon,each said brush being positioned for contact With a portion of one ofsaid segments at a time; a plurality of stationarily-mounted contacts,each of said plurality of contacts being connected to individual ones ofsaid input conductors and being mounted to bear on a corresponding oneof said rings; a front panel having its plane substantially parallel tothe longitudinal axis of said commutator; a brake portion for each ofsaid rings; a locking bar spring biased to engage each of said brakeportions and so to prevent rotation of said rings; a locking leveroperable from the front of said panel and having lock and unlockpositions, said locking lever being operative in said one look positionto counteract and maintain counteracted said spring bias on said lockingbar, thereby freeing said rings for rotation relative to saidcommutator, said locking lever being further operative in said lockposition to remove said counteraction of said spring bias and so to lockall of said rings against rotation; and a cover normally mounted againstsaid panel but movable for access to said panel, said cover beingpositioned and contoured to close against said panel only when saidlocking lever is in said locked position.

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